Flow controlled switching valve

ABSTRACT

A flow path switching valve is disclosed that can be operated remotely simply by turning flow on and off. A mid portion of the body has at least one passage therein leading from a central axial bore to one or more external ports each having a tractor nozzle. The valve outlet connects the axial bore to a cleaning nozzle. A poppet member is received in the central axial bore. In a first position, the poppet member directs fluid flow through the outlet to the cleaning nozzle connected to the outlet. The poppet member, when in a second position, closes the central axial bore through the outlet end of the valve body and permits fluid flow through the tractor nozzles. Selection of the different flow paths is made by simply reducing flow through the valve below a predetermined fluid flow threshold and then increasing the flow rate above the threshold.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.13/027,091, entitled Flow Controlled Switching Valve, filed Feb. 14,2011, now U.S. Pat. No. 8,667,987, the content of which is herebyincorporated by reference in its entirety.

BACKGROUND OF THE DISCLOSURE

Traction nozzles are used in sewer pipe lines and other piping systemsto assist in pulling high pressure hose into the pipe to reachobstructions requiring removal. These traction nozzles have jet tipsoriented at an angle rearward in order to generate thrust in the nozzlewithin the pipe to assist in pulling the hose through and along longstretches of pipe and around pipe bends. These nozzles have forwarddirected jet tips to ablate the obstructions encountered. However, theforward directed jet tips produce a counter force against forward travelof the nozzle through the pipe. This counterforce hinders effectivedeployment of the high pressure hose and reduces the net pulling forceproduced by the traction nozzle on the high pressure hose. Thus there isa need for a switching mechanism that does not generate a counterforceduring traction operation, yet facilitates operation of an effectivefluid jet nozzle during actual cleaning operations.

SUMMARY OF THE DISCLOSURE

The present disclosure directly addresses this problem. A switchingvalve in accordance with a first embodiment in the present disclosureprovides a simple valve device that switches, or redirects fluid flowbetween a first flow path such as to rearwardly directed nozzle jets anda second flow path, such as to forwardly directed cleaning jets,remotely. This is accomplished simply by decreasing fluid flow throughthe valve below a predetermined threshold level and then increasingfluid flow above the threshold level. The valve can provide fullpressure and fluid flow to each of the flow paths separately.

A valve in accordance with the present disclosure essentially has atleast two operative positions, analogous to operation of a retractableball point pen. One exemplary use of the valve is in sewer pipe cleaningwith water jet nozzles. In such a configuration the valve in accordancewith the present disclosure is installed between a cleaning nozzleassembly and a high pressure fluid hose sized to be inserted into asewer or other piping system.

The valve preferably includes a plurality of tractor nozzles arranged toprovide maximum pulling force to advance the hose, to which the valve isconnected, through the sewer piping system to a distant area needingcleaning. When the cleaning nozzle, attached to the front end of thevalve, arrives at the area needing cleaning, a temporary flowinterruption by the operator causes the valve to automatically switchfrom a first position directing fluid flow to the rearwardly directedtractor nozzles to an intermediate position. The valve automaticallyswitches from the intermediate position to a second position directingfluid flow to the forwardly directed cleaning nozzle or nozzles whenflow is restored. Another flow interruption causes the valve toreposition again to an intermediate position. Restoration of fluid flowabove the threshold again switches the valve back to the first positiondirecting fluid flow to the rearwardly directed tractor nozzles. Afurther flow interruption causes the valve to return to the intermediateposition. Restoration of fluid flow above the threshold causes the valveto again switch to the second position as above described. Thus eachtime the flow is interrupted and then restored causes the valve toswitch positions and hence flow paths.

One exemplary embodiment of the flow actuated flow path switching valveincludes a hollow valve body having an inlet end, an outlet end, a midportion, and a central axial bore through the inlet end, the midportion, and the outlet end. The mid portion has at least one passagetherein leading from the central axial bore through the valve body to atleast one external port having a tractor nozzle mounted therein. Anelongated poppet member is received, or carried, in the central axialbore of the valve body.

The poppet member has an open tubular rear end portion, a spool portionand a closed valve disc end portion. The poppet member can move axiallyback and forth in the central axial bore. The poppet member has an axialbore extending through the rear portion and at least part of the spoolportion of the poppet member. The spool portion has one or more radialarms extending outward to abut against the mid portion of the valvebody. The valve disc portion selectively closes the central axial borethrough the outlet end of the valve body when contact is made with aseat formed in the outlet end of the valve body.

A biasing member such as a spring is preferably positioned between thevalve body and the poppet member such that it resiliently biases thepoppet member toward the inlet end of the valve body. The spring is heldand compressed between a flange around the rear end portion of thepoppet member and a shoulder in the central axial bore through the valvebody. Fluid pressure and flow exerted on the rear end portion of thepoppet member compresses the spring to move the poppet member forward,away from the inlet end of the valve body. Reduction of fluidpressure/flow below a threshold permits the spring to push the poppetmember rearward.

The valve further includes a guide in the valve body that engages acorresponding feature on the rear end portion of the poppet member tochange orientation of the poppet member each time fluid flow through thevalve drops below a threshold value. Specifically, at a first positionof the poppet member, this guide and corresponding feature cooperate toalign the radial arm on the spool portion with the at least one passagein the mid portion of the valve body and open the central axial borethrough the outlet end of the valve body when fluid flow is introducedinto the inlet end of the valve body at the first position.

This guide also causes the poppet to rotate and misalign the radialpassage in the spool portion away from the at least one passage in themid portion of the valve body when fluid flow is reduced below thepredetermined flow rate threshold, to an intermediate position. Theguide is configured to align the arm of the spool portion at a secondposition different from the first position, also closing the centralaxial bore through the outlet end, when fluid flow is next introduced inthe inlet end of the valve body above the flow rate threshold. In thissecond position, fluid flowing around the arm of the spool portionenters and passes through the at least one passage in the mid portion ofthe valve body.

One exemplary embodiment of the valve has four radial arms on the spoolportion of the poppet and four passages through the mid portion of thevalve body leading to four rearwardly directed tractor nozzles. Thesetractor nozzles exit the valve body at a rearward angle. The reactionforce of the fluid jet exiting these nozzles pulls the valve and thehose connected thereto into the piping system. Fluid flows through thesenozzles when the valve is in the second position. When an obstruction isreached in the piping system, the operator simply turns off the flow,thus reducing flow below the threshold and the valve poppet movesrearward to an intermediate, or mid, position.

When flow is again restored by the operator turning flow back on, thepoppet moves forward, rotating via the guide, to the first position. Inthe first position, the radial arms are aligned with the passagesthrough the mid portion of the valve body, thus closing the passages. Atthe same time, the poppet is prevented from closing the outlet portion,thus permitting fluid flow past the poppet and out the outlet end of thevalve to the cleaning nozzle attached to the front end of the switchingvalve.

In a preferred embodiment, the poppet spool portion has a central boreand a passage leading from the central bore through each of the radialarms. In each passage through the radial arm is a stopper ball which,due to fluid pressure, completely plugs the passage through the midportion of the valve body such that no fluid can flow to the tractornozzles. These stopper balls ensure complete stoppage of fluid flowthrough the tractor nozzles when flow is being directed through thevalve outlet to the cleaning nozzle.

Further features, advantages and characteristics of the embodiments ofthis disclosure will be apparent from reading the following detaileddescription when taken in conjunction with the drawing figures.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external perspective view of one exemplary embodiment of aswitching valve in accordance with this disclosure connected between afluid hose and a cleaning nozzle.

FIG. 2 is a separate exploded perspective view of the switching valveshown in FIG. 1.

FIG. 3 is a longitudinal cross sectional view of the assembled switchingvalve body shown in FIG. 1 in accordance with the present disclosure,with the poppet and guide shown in perspective, in the first position.

FIG. 4 is a view as in FIG. 3 with the poppet in the second position.

FIG. 5 is a view as in FIG. 3 with the poppet in the mid, or low flow,position.

FIG. 6 is separate perspective view of the poppet shown in FIGS. 2-5,shown without the stopper balls in place, in accordance with the presentdisclosure.

DETAILED DESCRIPTION

An exemplary embodiment of a switching valve 100 is shown in FIG. 1connected to a high pressure fluid hose 102 and to a cleaning nozzle104. The switching valve 100 essentially has a generally cylindricalcompact outer shape so that it can be inserted into pipes and othertubular passages. A separate exploded perspective view of the valve 100is shown in FIG. 2. As shown in FIG. 2, the valve 100 includes a hollowmain valve body 106 and an inlet end guide cap 108. Inserted into themain valve body 106 is a spring 110 and a poppet member 112. Insertedinto the inlet end guide cap 108 is a guide collar 114 which carriesfour equally spaced guide pins 116. The inlet end guide cap 108 issealed with an O-ring 118 and threaded onto the valve body 106, thuscapturing together the poppet member 112, spring 110, guide collar 114with guide pins 116.

The inlet end cap 108, at its rear, may have internal threads 120 asshown or alternatively may have external threads to mate withcorresponding high pressure hose thread connections. The forward portionof the inlet end cap 108 has a recess to receive the guide collar 114and has internal threads so as to be screwed onto the rear portion ofthe main valve body 106.

The guide collar 114 is a tubular sleeve that has a pair of alignmentnotches 122 which engage corresponding projections 124 on the rearportion of the main valve body 106. The engaged projections 124 preventrotation of the collar 114 when assembled in the inlet end cap 108. Theguide collar 114 also has four radial bores 126 therethrough eachreceiving a guide pin 116 press fit therein. When the guide collar 114is assembled into the end cap 108, a portion of each of the guide pins116 projects radially inward toward the axial centerline of the end cap108.

The main valve body 106 is shown in cross section in FIGS. 3, 4 and 5.The valve body 106 is generally symmetrical about a central axis A. Thevalve body 106 has a an inlet end 128, an outlet end 130, a mid portion132, and a central axial bore 134 through the inlet end 128, the midportion 132, and the outlet end 130. The mid portion 132 has an enlargedflange external shape and has at least one passage 136 therein leadingfrom the central axial bore 134 through the valve body 106 to at leastone external port 138. In the exemplary embodiment of the valve 100shown, there are four passages 136, equally spaced radially apart by90°, leading to four external ports 138. Threaded into each externalport 138 is a nozzle jet tip 140. Each of the external ports 138 isrearwardly directed at an angle such that forward thrust is exerted onthe valve 100 when high pressure fluid is ejected through the nozzle jettips 140 to push the valve, attached hose 102, and cleaning nozzle 104through piping to the location needing to be cleaned. Note that, in theexemplary embodiment shown, there are four passages 136. Other valvebody configurations are also envisioned, such has a valve body havingany number of radial passages in the mid portion 132 of the valve body106 leading to a corresponding number of ports 138, each having anappropriate nozzle jet tip 140 attached thereto.

The bias member 110 is a spring, such as a coil spring, and morepreferably a flat wire wave compression spring that is captured betweenan internal shoulder 142 in the mid portion 132 of the valve body 106and an annular flange 144 on the poppet member 112. This spring biasmember 110 urges the poppet member 112 rearward toward the inlet end ofthe valve 100 in the absence of fluid pressure and flow. When fluid flowis introduced into the valve 100, the spring bias member 110 iscompressed, urging the poppet member 112 forward as is described in moredetail below.

The poppet member 112 is separately shown in FIG. 6. The poppet member112 is a generally elongated body generally symmetrical about a centralaxis A. The poppet member 112 has an open tubular rear end portion 146,a spool portion 148 and a closed end valve disc portion 150. The disc151 of the valve disc portion 150 selectively closes the central axialbore 134 through the outlet end 130 of the valve body 106. The poppetmember 112 has an axial bore 152 extending through the rear portion 146and part of the spool portion 148 of the poppet member 112. The spoolportion 148 has one or more radial arms 154, preferably an even number,and in the illustrated exemplary embodiment, four radial arms 154,extending outward radially from a central stem 156 of the spool portion148 to the inner wall of the mid portion 132 of the valve body 106. Thespool portion 148 of the poppet member 112 also has several ports 158leading forward from the bore 152 out of the rear portion 146. Theseports 158 permit fluid flow through the bore 152 and around the arms 154to and past the disc 151 of the closed end valve disc portion 150 of thepoppet 112 and through the outlet 130 of the valve body 106 when thepoppet 112 is in the second position.

Each of the radial arms 154 has a central passage 160 therethrough.Furthermore, each of the passages has a ball 162 disposed therein (shownin FIGS. 2 & 3). When the valve 100 is in the first position, shown inFIG. 3, the radial arms 154 are aligned with the passages 136. As fluidflows through the passages 160 into the passages 136, the balls 162 seatto close and block any further flow through passages 136. Fluid alsoflows through the axial bore 152 and through the ports 158, around theradial arms 154, and then to the outlet end 130 of the valve body 106around the closed end valve disc portion 150. This configuration isshown in FIG. 3.

Turning back now to FIG. 6, and the separate view of the exemplarypoppet 112, the open rear end portion 146 of the poppet 112 will bedescribed. The end portion 146 has a tubular side wall 164 that has azig-zag pattern annular cam groove 166 formed in the tubular wall 164.This cam groove 166 is sized complementary to the diameter and depth ofthe pins 116 and has forward notches or vertices 168 each rotationallyspaced about 45° apart along the groove 166. The cam groove 166 also hasrear notches 170 spaced alternatingly with four axial grooves 172 spaced90′ apart. These axial grooves 172 merge with the cam groove 166 at anangular rotation position between the rear notches 170 in the groove166.

Each of the four guide pins 116 ride in the cam groove 166 when thevalve 100 is fully assembled. The sides of the cam groove 166 are angledtoward the sequential forward and rear notches or vertices 168 and 170of the groove 166 such that when the poppet moves forward and back asflow is applied or reduced, the poppet 112 has to rotate 22.5° clockwiseeach time as it moves forward or back with each change in flow above andbelow the predetermined threshold rate.

When fluid flow is off, or at least reduced below the predeterminedthreshold, established by the spring rate of the spring 110, the poppet112 moves rearward to one of the intermediate positions as is shown inFIG. 5. In this intermediate, or mid position, the radial arms 154 ofthe spool portion 148 are offset from alignment with the passages 136rendering the passages 136 open to the bore 134 through the main valvebody 106. Also, the disc portion 150 is spaced from the seat of theoutlet end 130 of the valve body 106.

If the position of the poppet 112 before flow decrease had been as shownin FIG. 3, (flow through the outlet to the cleaning nozzle 104), then,when fluid flow is again turned on, the poppet 112 again is movedforward by the fluid flow against the inlet end portion 146, but thistime moves the poppet 112 to the position shown in FIG. 4. This is thesecond position, in which the arms 154 are not aligned with the passages136 through the mid portion of the valve body 106, and the disc 151 ofthe closed end valve disc portion 150 closes the outlet 130. Fluid flowthus is free to pass through the axial bore 152 in the rear end portionof poppet 112, through the passages 158 out of the stem 156 of spoolportion 148, around the arms 154, and through the passages 136 to theexternal ports 138 and tractor nozzle jet tips 140.

When flow is subsequently reduced below the predetermined threshold,such as by the operator turning off flow, the poppet 112 rotatesrearward to a position similar to that shown in FIG. 5, except rotatedone notch 168 further by 45° than that shown. When flow is againrestored, the poppet 112 continues to rotate, forward this time, to aposition identical to that shown in FIG. 3.

It is to be understood that various changes can be made to the switchingvalve 100 in accordance with the present disclosure. For example, thevalve body may be configured with 2, 3, 4, 5, or 6 radial passages 136,and the corresponding poppet would thus have an equal number of properlyspaced radial arms 154. Furthermore, if sufficiently close tolerancesare maintained, the need for balls 162 and passages 160 through theradial arms 154 may be eliminated. In such a configuration, the radialarms 154 would be solid and configured to substantially close off thepassages 136 to the external traction ports 138.

Alternatively different sets of ports could be provided in the valvebody 106 to provide additional flow paths as may be needed for aparticular application. For example, rather than having only twoseparate flow paths, a configuration that has three flow paths could bedesigned without departing from the scope of the present disclosure. Insuch a configuration the zig-zag guide groove would have a differentnumber of notches 168 and 170 as would be required for such aconfiguration. The passages 136 could alternatively lead to a separatenozzle assembly fastened to the valve rather than having integraltractor jet tips 140 mounted directly to the valve body 106.Furthermore, jet tool nozzle configuration and/or patterns can beselected to control speed or direction.

Fluid flow may alternatively be directed to other end components ratherthan nozzles. For example, in other applications of the valve 100disclosed herein, the fluid flow could be directed not to nozzles, butto actuators which could perform functions such as centralizing,clamping, bending, crushing, expanding, or plugging. Thus theimplementation to which the switching valve 100 is applied may besubstantially modified.

All such changes, alternatives and equivalents in accordance with thefeatures and benefits described herein, are within the scope of thepresent disclosure. Such changes and alternatives may be introducedwithout departing from the spirit and broad scope of my invention asdefined by the claims below and their equivalents.

What is claimed is:
 1. In a piping cleaning apparatus having a highpressure fluid cleaning nozzle attached to a flexible hose for passagethrough a length of piping to a location requiring cleaning, a flowactuated switching valve connected between the hose and the cleaningnozzle, the switching valve comprising: a valve body having an inletportion configured to be connected to the hose, a mid portion, an outletportion configured to be connected to the cleaning nozzle, and a centralaxial bore therethrough, the mid portion having a plurality ofrearwardly directed ports connected by passages to the central axialbore; an elongated poppet member slidably disposed in the central axialbore, the poppet member having a rear portion, a spool portion forselectively opening and closing the passages in the mid portion of thevalve body and a closed end portion forming a valve disc for closing theoutlet portion of the valve body; a bias member between the poppetmember and the valve body biasing the poppet member rearward; and aguide member between the rear portion of the poppet member and the valvebody for guiding the poppet member between first and second rotarypositions when fluid flow through the valve drops below a predeterminedflow rate threshold and then returns above the flow rate threshold. 2.The flow actuated switching valve according to claim 1 wherein the valvedisc of the poppet member engages a complementary valve seat in thevalve body closing the central axial passage when the poppet member isin the second position.
 3. The flow actuated switching valve accordingto claim 2 wherein when fluid flow is again reduced below thepredetermined threshold the valve disc of the poppet member disengagesthe valve seat and opens the central passage through the outlet portionof the valve body.
 4. The flow actuated switching valve according toclaim 3 wherein when fluid flow is again increased above thepredetermined threshold the guide causes the poppet member to againreturn to the first position.
 5. The flow actuated switching valveaccording to claim 1 wherein the poppet member has an axial boreextending through the rear portion and the spool portion of the poppetmember and the spool portion has at least one or more radial armsextending to the mid portion of the valve body.
 6. The flow actuatedswitching valve according to claim 5 wherein the at least one armincludes a radial passage from the axial bore to the end of the arm. 7.The flow actuated switching valve according to claim 6 furthercomprising a ball disposed in the radial passage for sealing the passagethrough the mid portion of the valve body when the poppet member is inthe first position.
 8. The flow actuated switching valve according toclaim 1 wherein the poppet member has a plurality of bypass passagesleading from the rear end portion around the axial bore in the spoolportion.
 9. The flow actuated switching valve according to claim 5wherein the poppet member has a plurality of bypass passages through therear end portion around the central axial bore in the spool portion. 10.The flow actuated switching valve according to claim 1 wherein the firstposition blocks fluid flow through the passage through the mid portionof the valve body and permits fluid flow through the valve body from theinlet end, around the spool portion of the poppet member, and outthrough the valve body outlet end.
 11. The flow actuated switching valveaccording to claim 1 wherein the second position permits fluid flowthrough the passage in the mid portion of the valve body.
 12. The flowactuated switching valve according to claim 1 wherein the guide membercauses the poppet member to rotate when moving between the first andsecond positions.
 13. The flow actuated switching valve according toclaim 1 further comprising the poppet member being held at a thirdposition when flow is reduce below the threshold.
 14. The flow actuatedswitching valve according to claim 1 wherein the guide member includes astationary pin projecting radially inward from an inside surface of thevalve body into a complementary groove formed in the rear end portion ofthe poppet member.
 15. The flow actuated switching valve according toclaim 14 further comprising at least two spaced stationary pinsprojecting into complementary grooves formed in the rear end portion ofthe poppet.
 16. The flow actuated switching valve according to claim 4wherein the guide member includes two or more spaced stationary pinsprojecting radially inward from an inside surface of the valve body intoa complementary groove formed in the rear end portion of the poppetmember.
 17. The flow actuated switching valve according to claim 16wherein the guide member includes four equally spaced stationary pinsand the complementary groove causes the poppet body to rotate about 45degrees between each of the first and second positions.
 18. In a pipingcleaning apparatus having a high pressure fluid cleaning nozzle attachedto a flexible hose for passage through a length of piping to a locationrequiring cleaning, a flow actuated switching valve connected betweenthe hose and the cleaning nozzle, the switching valve comprising: ahollow valve body having an inlet end, an outlet end, a mid portion, anda central axial bore through the inlet end, the mid portion, and theoutlet end, the mid portion having at least one passage therein leadingfrom the central axial bore through the valve body to at least oneexternal port; a poppet member received in the central axial bore, thepoppet member having an open tubular rear end portion, a spool portionand a closed end valve disc portion, the valve disc portion selectivelyclosing the central axial bore through the outlet end of the valve body,the poppet member having an axial bore extending through the rearportion and the spool portion of the poppet member, the spool portionhaving at least one or more radial arms extending to the mid portion ofthe valve body; a biasing member between the valve body and the poppetmember biasing the poppet member toward the inlet end of the valve body;and a guide member between the rear end portion of the poppet member andthe valve body for guiding the poppet member between first and secondrotary positions when fluid flow through the valve drops below apredetermined flow rate threshold and then returns above the flow ratethreshold.
 19. The flow actuated valve according to claim 18 wherein thevalve disc portion of the poppet member engages a complementary valveseat in the valve body closing the central axial passage when the poppetmember is in the second position.
 20. The flow actuated valve accordingto claim 19 wherein when fluid flow is again reduced below thepredetermined threshold the valve disc portion of the poppet memberdisengages the valve seat and opens the central passage through theoutlet end of the valve body.